Self-dispersing particulate composition and methods of use

ABSTRACT

A self-dispersing particulate composition, in the form of pellets, prills, flakes or granules, containing particles with a first functional component that is a glassy solid with small, dispersed pockets of pressurized gas and, in the same or different particles, a second functional component that is a special-use material having at least one additional utility. Special use materials include, for example, a deicer, a fertilizer, a drain cleaner, an insecticide, a carpet cleaner, and a powdered laundry detergent. Dissolution of the glassy material liberates pressurized gas, causing repositioning of the special-use material.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to self-dispersing particulate materials, andmore particularly, to self-dispersing particulate materials containingpressurized gas that is trapped in discrete cavities or pockets inside acontinuous matrix. The matrix material is solid prior to use but ispartially dissolved during use to spontaneously liberate pockets of theentrapped, pressurized gas. When liberated during use, the gas exertssufficient force to propel or rapidly reposition the particle from whichthe gas is expelled. This repositioning causes random scattering anddispersion of the particulate material. Useful applications for thecomposition include, for example, deicers, drain cleaners, fertilizers,insecticides, floor cleaners, and the like.

2. Description of Related Art

The use of particulate deicers such as mineral salts for melting ice andsnow is well known. Such particulate materials are typically scatteredby hand or with a broadcast-type spreader over an icy surface.Unfortunately, the coverage achieved with such distribution methods isoften irregular, especially when the materials are broadcast manually.Ice contacted by the deicer particles typically melts in a crater aroundthe particle, forming a small pool of water that can insulate theparticle from further contact with the surrounding ice, thereby slowingmelting. Although liquid deicer compositions are also available andprovide good coverage, they are most often applied using mechanicalsprayers and often exhibit the associated disadvantage of producing asurface that is more slippery, and therefore more hazardous topedestrian or vehicular traffic, than an icy surface having aparticulate mineral composition scattered over it. A dry particulatedeicer composition is therefore needed that includes at least onecomponent capable of melting ice and at least one other componentcapable of continually dispersing and redistributing the meltingcomponent across an icy surface to achieve improved particle dispersion.Other systems for thermochemical ice melting are disclosed in U.S. Pat.No. 5,176,210. Prior art patents such as, for example, U.S. Pat. Nos.3,012,893, 3,985,909 and 3,985,910, disclose the manufacture of flavoredand colored, gas-containing, candy particles that “pop” or “explode”whenever entrapped pockets of compressed carbon dioxide gas areliberated as the sugary material dissolves upon contact with saliva orother liquids. Generally speaking, such candies are made by injectinggas into heated sugar syrup while under pressure, thereafter cooling tosolidify the syrup, releasing the pressure and fracturing the glassycandy into particles. Such novelty items do not, however, serve anyother beneficial purpose or perform any other function or utility thatis worthwhile in connection with other consumer, commercial,governmental, institutional, industrial, recreational or environmentalneeds or objectives.

Other prior art relating to gasified candies and methods and apparatusfor making them include, for example, U.S. Pat. Nos. 4,001,457;4,262,029; 4,273,793; and 4,289,794.

SUMMARY OF THE INVENTION

The self-dispersing particulate composition of the invention isdesirably a product in the form of pellets, prills, flakes or granulesthat comprises particles containing a first functional component capableof releasing pressurized gas in combination with particles containing asecond functional component, or special-use component, having at leastone additional utility. Such additional utilities can vary widely,depending upon the chemical makeup of the special-use component, and caninclude, for example, the capability for functioning as a deicer, afertilizer, a drain cleaner, an insecticide, or the like. According toone embodiment of the invention, the subject composition is a mixture ofdispersing particles and special-use particles. According to another,particularly preferred, embodiment of the invention, the subjectcomposition contains only a single type of particle, which embodies boththe self-dispersing and special-use components.

The advantages of using the self-dispersing particulate compositions ofthe invention in comparison to other conventional, commerciallyavailable products can vary according to the particular use that isintended. Where the special-use component is a deicer, for example, thedispersing component causes the special-use component to be spread toother nearby areas where no melting has yet occurred. Besides deicers,other commonly used products consisting of particulate materials canalso be made more effective by providing an innate or collateral abilityfor the particles to randomly reposition themselves during use. Suchproducts can include, for example, particulate fertilizers,insecticides, and the like. In other applications, such as where thespecial-use component is a drain cleaner, the pressurized gas releasedby particles containing the dispersing component at the point of use,such as inside a P-trap, can assist in dislodging matter clogging thedrain as it is being dissolved or otherwise acted upon by thespecial-use component.

According to one preferred embodiment of the invention, aself-dispersing particulate product intended for use as a deicer, thecomposition comprises particles having a solid phase containing analkaline earth metal salt such as calcium chloride or magnesium chloridedissolved or dispersed in a glassy, sugary material, and finely dividedbubbles of pressurized gas disposed within the fused, glassy material.During use of the subject composition, the particles are initiallyscattered across an icy surface to be treated. As melting occurs due tohydration of the salt, the resultant water also causes the glassy,sugary material to begin dissolving away, eventually exposing pockets ofpressurized gas disposed inside the particles. As the glassy part of theparticles begins dissolving, pressurized gas escapes forcibly from eachsuccessively exposed cavity in which it was previously entrapped duringmanufacture. This successive, forcible liberation of gas from cavitiesinside the particles, as the wall around each cavity dissolves,repeatedly causes the particles to be propelled to other positions,sometimes inches or even feet away. For illustrative purposes, theresultant effect is similar to the way popcorn kernels are propelledwhen moisture inside them is vaporized during cooking, causing thekernels to “pop” around to different positions. The subject compositionis useful for melting ice from surfaces such as sidewalks, steps, ramps,roadways, runways, bridges and the like. Alternatively, the dispersingand special-use components can be disposed in different particles, whichare then intermixed to form the subject composition.

According to another embodiment of the invention, the dispersingcomponent of the subject composition preferably contains sufficientfinely divided, dispersed, trapped, compressed gas that, when liberatedupon contact with moisture, the gas will exert a force adequate to movethe particle from which the propellant is released to a differentposition on an underlying surface. Although not preferred, dispersingcomponents can also be made that contain reactants capable of rapidlygenerating a quantity of pressurized gaseous propellant that issufficient to relocate or reposition a particle when contacted bymoisture or another substance present in the use environment.Preferably, the force generated through release of the propellant willbe sufficient to relocate the propelled particle a distance that is atleast several times the maximum particle dimension. When the dispersingcomponent and the special-use component of the invention are containedin separate particles, the particles containing the dispersant willdesirably move with sufficient momentum when activated to collide withparticles containing the special-use component and cause repositioningof those particles as well. In the latter case, the use of from at leastabout 5 to about 50 percent or more, and most preferably from about 10to about 25 percent, dispersing particles is believed to be desirablefor promoting a suitable level of physical interaction with particlescontaining the special-use component. It will be appreciated, however,that even more dispersing particles can be needed, depending upon thedegree to which particles are scattered during application.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A self-dispersing particulate composition is disclosed herein thatcomprises at least first and second functional components, which firstand second components can be disposed in the same or differentparticles. The particles themselves can take the form of pellets,prills, flakes or granules, and where the first and second componentsare disposed in different particles, the particle form can be differentfor the different particles. Thus, for example, the first functionalcomponent can be present in particles having the form of granules whilethe second functional component is present in particles having the formof flakes.

The first functional component of the compositions of the invention ispreferably a self-dispersing particle containing either a pressurizedgas or a material that, when contacted with a reactive liquid, producesa pressurized gas. As used herein, the term “self-dispersing” refers tothe tendency of a particle to move and reposition itself whenevercontacted and acted upon by another substance, such as moisture, so asto expose cavities containing pressurized gas and thereby liberate thegas. As used herein, the term “pressurized gas” means a gas that isliberated at a pressure or rate that is sufficiently high to producemovement and repositioning of the particle from which the gas isliberated. According to a particularly preferred embodiment of theinvention, small pockets of gas at a pressure substantially greater thanatmospheric, most preferably on the order of several hundred pounds persquare inch, are dispersed and confined inside the particle duringmanufacture. The particles in which the pressurized gas is entrapped arepreferably made of a glassy material such as, for example, sugar-basedcompositions comprising cane sugar, corn syrup, sucrose, lactose, andmixtures thereof. A particularly preferred gas for use in theself-dispersing particles of the invention is carbon dioxide. Accordingto conventional methods known to those of skill in the art, suchparticles can be made by injecting the pressurized gas into the bottomportion of a reactor containing a heated, viscous sugar solutionundergoing rapid agitation so that the gas bubbles become finely dividedand distributed throughout the solution. The solution is thereaftercooled under pressure to solidify and fuse the sugar into a solidcontaining entrapped bubbles of compressed gas dispersed throughout acontinuous matrix of glassy, solidified sugar. The resultant mass can befragmented into particulate form by releasing the pressure on thereactor, or by any other suitable means or combination of additionalprocessing steps, which can include pressure reduction, hammering,screening, or the like. The fragmented particles are desirablymaintained in a dry or low humidity environment at temperatures lowerthan about 38° C. until the time of use to prevent clumping or meltingthat could cause the premature release of pressurized gas from theparticles.

Sugar-based compositions are particularly preferred for use as theglassy material where water is present in the use environment becausecontact with water will cause the glassy material to begin dissolvingand thereby uncover bubbles or pockets of pressurized gas. Similarly,where non-aqueous solvents are present in the intended use environment,a different glassy material that is soluble in such other solvents canalso be employed within the scope of the invention. Although carbondioxide is a preferred gaseous component for use in the self-propellingparticles of the invention, it should be appreciated that other gasessuch as air and nitrogen can be similarly used, provided they are safefor the intended application.

The second functional component of the compositions of the invention ispreferably a special-use material that can be disposed in the sameparticles as the pressurized gas component or can be disposed in otherparticles that are intermixed with the self-dispersing particles toproduce the subject compositions. As used herein, the term “special-use”means any utility or application beyond those achieved through use ofthe first component alone. Special-use materials suitable for inclusionas the second functional component, also referred to herein as thespecial-use component of the invention, can include compositions thatare themselves useful as, for example, deicers, fertilizers,insecticides, drain cleaners, carpet cleaners, powdered laundrydetergents and the like. In compositions of the invention wherein thefirst and second functional components are present in the same particle,the special-use component is preferably a compound that is soluble orreadily dispersible in, and substantially non-reactive with, the glassymaterial used in making the first functional component. In compositionsof the invention wherein the first and second functional components aredisposed in separate particles that are intermixed, and wherein theglassy material used in the first component is water soluble, thespecial-use component is preferably a compound that is non-reactive withthe glassy material used in making the first functional component.Because moisture can cause sugary solids to stick, clump and partiallydissolve, such compositions of the invention are desirably packaged inmoisture resistant bags or containers, and can also contain a desiccantwhere needed.

One particularly preferred composition of the invention is useful fordeicing surfaces such as sidewalks, driveways, steps, porches, and thelike. Particles containing the first functional component of theinvention are preferably made by combining a sugary material with aminor amount of liquid, which may be present as a hydrate, but istypically water in an amount constituting about one weight percent ofthe total, that is effective for forming a solution. The excess watermay be removed under vacuum. The resultant solution is heated to atemperature of about 100 to about 150° C. inside a closed, stirredreactor; injecting pressurized carbon dioxide into the stirred solutionto effect the dispersion of small bubbles of gas throughout thesolution, until the solution is substantially saturated with the gas andthe pressure inside the reactor is about 600 psi; cooling the reactor toa temperature ranging between about 22 and about 4° C. while still underpressure to solidify the solution; and thereafter releasing the pressureinside the reactor, causing the gasified, glassy, solid material insidethe reactor to fracture into particles. During cooling, the pressureinside the reactor may drop to about 400 psi. When the reactor pressureis released and the solid mass fractures, some portion of the previouslyentrapped gas is released, although nearly all of the particles thusproduced will still contain pockets of pressurized gas entrapped withinvoids or cavities inside the glassy solid. If the solution is gasifiedat pressures substantially higher than about 600 psi, the glassy solidmay fracture too much when pressure is released; whereas, ifgasification is conducted at pressures substantially lower than about600 psi, insufficient fracturing can occur upon depressurization.Additional screening and fragmentation by other conventional mechanicalmeans can be used if needed to obtain a desired particle sizedistribution. Preferred particle sizes for the ice melting component ofthe invention range from about 0.1 mm to about 8 mm, and mostpreferably, from about 1 mm to about 4 mm.

If the temperature of the solution inside the reactor is permitted toclimb higher than about 150° C., undesirable caramelization orcarbonization of the sugary material can occur. The pressurized gasentrapped in the glassy solid will typically cause the solid to fractureinto particles of usable size when pressure inside the reactor isreduced. At the same time, the solid material will undergo a volumeexpansion due to the lower bulk density of the particulate material. Ifdesired, the pressurized, gasified sugary solution can be pumped ordrained from the reactor into other vessels and maintained underpressure during cooling to permit reuse of the reactor prior tocompletion of the process.

Similarly sized particles containing the second functional component arethereafter preferably intermixed with the self-dispersing particlesprior to packaging. According to one preferred embodiment of theinvention, where the first and second functional components are embodiedin different particles of the composition, the ratio of particlescontaining the first functional component to particles containing thesecond functional component will desirably range from about 1:20 toabout 1:1, with particle ratios ranging from about 1:10 to about 1:3being most preferred. It is emphasized, however, that a particularnumerical correspondence between special-use particles andself-dispersing particles is not required so long as the size and numberof self-dispersing particles are sufficient to promote contact with andachieve the desired random redistribution of particles containing aspecial-use component. Preferred materials for use as the secondfunctional component of the deicer composition described above includecalcium chloride, magnesium chloride, calcium magnesium acetate, sodiumacetate, urea, and mixtures thereof, whether in pellet, prill, flake orgranulated form. The use of calcium chloride and/or magnesium chlorideis particularly preferred, although magnesium chloride is significantlymore expensive than calcium chloride. Although the use of anhydroussalts will help keep water-soluble glassy materials from becoming moistand sticking, the use of selected exothermic hydrated salts is alsobelieved to accelerate melting. In some cases, the addition of asurfactant is also believed to promote effectiveness of thecompositions. If desired, the particles containing the second functionalcomponent can also comprise a filler material or extender, or anotherspecial-purpose additive.

According to another preferred embodiment of the invention, the secondfunctional component is added directly to the solution of glassymaterial prior to gasification. Although either anyhydrous or hydratedsalts may be used as the second functional component as shown in theprior embodiment, the use of hydrated salts may provide excess waterwhich may be removed by vacuum prior to heating in the reactor. In thisembodiment of the invention, unlike the embodiment wherein the secondfunctional component is in a separate particle, it is important that thedeicer component be either soluble or easily dispersible in the solutionof glassy material. Typically, the second functional component isnon-reactive either with the glassy material or with the pressurized gasthat is injected into the solution of glassy material duringmanufacture. Where the dispersing component is a sugary material and thespecial-use component is a salt such as calcium chloride, the salt willtypically be readily dispersible throughout the sugar solution. Otherspecial-use components such as urea or sodium acetate, on the otherhand, are typically soluble in the sugar solution. In either case, thecombined sugary liquid and special-use component are referred to hereinas a “solution.”

In the preferred single-particle deicer composition of the invention,the amount of deicer component that is added to the sugary solution willdesirably constitute from about 15 to about 35 weight percent, and mostpreferably from about 20 to about 30 weight percent, of the combinedsolution. Examples of deicer compositions made in accordance with theinvention are set forth below.

EXAMPLE 1

A sugary solution comprising about 79 weight percent cane sugar, about20 weight percent urea (0.6 hydrate) and about 1 weight percent water isprepared in a Parr reactor having a paddle-type stirrer and substantialheadspace over the solution. The temperature is gradually increasedwhile stirring at 1250 rpm or greater, and is controlled within a rangeof from about 100 to about 135° C. while injecting carbon dioxide intothe solution through a tube discharging approximately ¼ inch from thebottom until the solution is substantially saturated with finely dividedbubbles of dispersed gas and the pressure inside the reactor is about600 psi. Stirring is then stopped and the reactor is cooled to atemperature ranging between about 22 and about 4° C., during which timethe reactor pressure falls to about 400 psi and a fused, glassy solid isformed. After cooling, the reactor is opened and the solid massfractures, producing a larger bulk volume of small, irregularly shapedparticles that are easily removed from the reactor. The resultantparticles are scattered manually over an ice-covered driveway. Asmelting commences, water is observed forming around the particles,followed by “popping” or random repositioning and relocation of theparticles over the surface of the ice, with continued melting in eachlocation where the relocated particles come to rest.

EXAMPLE 2

Particles are prepared as for Example 1 except that the solution insidethe reactor comprises about 79 weight percent sugar, about 10 weightpercent urea (0.6 hydrate), about 10 weight percent calcium chloride,and about 1 weight percent water. The resultant particles are againscattered manually over an ice-covered driveway. As melting commences,water is observed forming around the particles, followed by “popping” orrandom repositioning and relocation of the particles over the surface ofthe ice, with continued melting in each location where the relocatedparticles come to rest.

EXAMPLE 3

Particles are prepared as for Example 1 except that the solution insidethe reactor comprises sugar and calcium chloride in a weight ratio ofabout 70% to about 30%, together with a minor amount of water. Theresultant particles are again scattered manually over an ice-covereddriveway. As melting commences, water is observed forming around theparticles, followed by “popping” or random repositioning and relocationof the particles over the surface of the ice, with continued melting ineach location where the relocated particles come to rest.

EXAMPLE 4

Particles are prepared as for Example 1 except that the solution insidethe reactor comprises about 70 weight percent sugar and about 30 weightpercent sodium acetate trihydrate. Water is provided by the sodiumacetate trihydrate, which contains 39.7% water by weight. The excesswater is removed by vacuum prior to heating. The resultant particles areagain scattered manually over an ice-covered driveway. As meltingcommences, water is observed forming around the particles, followed by“popping” or random repositioning and relocation of the particles overthe surface of the ice, with continued melting in each location wherethe relocated particles come to rest. The use of sodium acetatetrihydrate forms a lower viscosity melt in which gasification can beperformed at a lower temperature than is required, for example, wherecalcium or magnesium chloride is the special-use component.

EXAMPLE 5

A sugary solution comprising about 90 weight percent cane sugar andabout 10 weight percent corn syrup is formed in a stirred Parr reactoras described above. The reactor is closed and the temperature isgradually increased while stirring, and is controlled within a range offrom about 100 to about 135° C. while injecting carbon dioxide into thesolution until the solution is substantially saturated with the gas andthe pressure inside the reactor is about 600 psi. Stirring is thenstopped and the reactor is cooled to a temperature between about 22 andabout 4° C., during which time the reactor pressure falls to about 400psi and a fused, glassy solid is formed. After cooling, the reactor isopened and the solid mass fractures, producing a larger bulk volume ofsmall, irregularly shaped particles that are easily removed from thereactor. The resultant particles are mixed with similarly sizedparticles of substantially anhydrous calcium chloride in a ratio ofabout 1:3, and the resultant mixture is scattered manually over anice-covered driveway. As melting commences, water is observed formingaround the particles of calcium chloride. As melt water begins toaccumulate on the surface of the ice and contacts particles of thegasified, sugary solid, “popping” or random repositioning and relocationof the sugary particles is observed. This “popping” of the sugaryparticles is observed to cause collisions with calcium chlorideparticles scattered nearby, resulting in repositioning and relocation ofthe calcium chloride particles over the surface of the ice, withcontinued melting in the location where each such relocated deicerparticle comes to rest.

The deicer compositions disclosed herein are believed to provide severalvaluable advantages over conventional, commercially available broadcastdeicer products. One advantage relates to the “self-spreading” featureas already described. Another relates to the faster rate at which thespecial-use component is dissolved during use, especially when combinedinto a single, sugary particle containing the pressurized gas. Stillanother advantage relates to the tendency of the self-dispersingcomponent to “stir” the thermally stratified melt water that forms incraters around the deicer component, thereby circulating warmer water atthe top of the melt water pool to the underlying ice and furtheraccelerating melting. Finally, in addition to promoting melting byscarifying and pitting the underlying icy surface, the subject deicercompositions simultaneously improve traction for a user, therebyreducing slippage and resultant injury during ice removal.

While the preferred compositions of the invention and a preferred methodfor making them are disclosed herein, it should be understood that othercomponents and methods satisfactory for use in making the gasified,fused, glassy material that is the first functional component of theinvention are more completely described, for example, in U.S. Pat. Nos.3,012,893; 3,985,909; and 3,985,910, the specifications of which areincorporated by reference herein. These references disclose, forexample, that candy glasses containing from about 2.5 to about 15 ml,and preferably from about 4 to about 6 ml of carbon dioxide per gram,produce satisfactory results; that stirring speeds over 1200 rpm arepreferred in order to incorporate greater amounts of gas into theproduct; and that a relatively large headspace should be maintainedabove the level of the melt inside the vessel in order to achieve thedegree of turbulence needed to divide the gas bubbles into minutedimensions. Mixing times ranging from about 2 to about 6 minutes aretypically needed in order to obtain the desired saturation anddispersion of gas, depending upon the composition, temperature andviscosity of the solution. Although the compositions of the inventionare described above in relation to the preferred embodiment of a deicer,it is believed that compositions having other beneficial uses can bemade in substantially the same manner using the inventive conceptsdisclosed herein, but with different special-use components. If intendedfor use in an environment where the product is likely to encounter waterbefore reaching the optimal use site, or where a time-delay effect isdesired, some or all of the particles can be coated or encased in agelatin shell that will delay liberation of the pressurized gas evenafter the product is contacted by water. Variable delay intervals arelikewise achievable through the use of different coating materialsand/or thicknesses.

One beneficial product within the broader scope of the invention is afertilizer product made by combining a dispersing component the same as,or similar to, that described above in combination with a special-usecomponent that comprises salts of conventional fertilizer componentssuch as nitrogen, potassium and phosphorus. The use of a sugarydispersant can also promote the growth of useful microorganisms withinthe soil, thereby enhancing the effectiveness of the fertilizer.

Another beneficial product made within the broad scope of the inventionis a two-component drain cleaner. In this application of the disclosedinvention, the special-use component can be any commercially availabledrain cleaning substance that is compatible with the self-dispersingcomponent. If needed, and especially where the special-use component iscontained in separate particles, gelatin coatings can be used to delayactivation of the self-dispersing component until the special-usecomponent has been given time to act, for example, inside the P-trap ofa standard drain. Once the special-use component has softened orchemically degraded the clogging matter inside the drain, activation ofthe self-dispersing component to liberate pressurized gas at the usesite can assist in dislodging and displacing the clogging matter.

Another beneficial product made within the broad scope of the inventionis a fire ant insecticide product. The effectiveness of a conventionalinsecticide composition known to be useful in treating fire ant moundscan be further enhanced by combining it with a self-dispersing componentaccording to the present invention. The liberation of carbon dioxideinside the mound is believed to cause ants to lose consciousness, andsome additional subsurface scattering of the special-use component isalso achieved.

Another beneficial product made within the broad scope of the inventionis a carpet shampoo that uses the mechanical energy of the gas liberatedfrom the self-dispersing component to penetrate the carpet pile,dislodge grime and otherwise promote cleaning.

Another beneficial product made within the broad scope of the inventionis a powdered laundry product that exhibits a release of energy in theform of pressurized gas even when a washing machine is filling withwater prior to commencing agitation. The powdered laundry product of theinvention preferably comprises an admixture of a dispersing component asdescribed above in combination with particles of a conventional powderedlaundry detergent.

While the first functional component of the invention preferablycomprises either a compressed gas trapped inside a water-soluble, glassysolid, other embodiments can utilize reactants that will explosivelygenerate a gas in situ when contacted by water or another material thatis present in the use environment. With either propellant embodiment ofthe invention, sufficient gas should be forcibly released or expelledfrom the particle to cause rapid acceleration of the particle away fromits initial position on the underlying surface, most preferably to aposition that is farther away from the initial position than severaltimes the maximum external dimension of the particle. This movementproduces collisions with other particles containing the ice meltingcomponent, causing them to be redistributed.

Other alterations and modifications of the invention will likewisebecome apparent to those of ordinary skill in the art upon reading thepresent disclosure, and it is intended that the scope of the inventiondisclosed herein be limited only by the broadest interpretation of theappended claims to which the inventors are legally entitled.

What is claimed is:
 1. A deicer composition comprising a plurality ofparticles, at least some of the particles comprising an ice-meltingcomponent that, when contacted with ice, reacts chemically with the iceto produce melt water, and at least some of the particles furthercomprising a self-dispersing component containing a glassy solid withdispersed pockets of confined, pressurized gas that, when partiallydissolved upon contact with melt water, liberates pressurized gas at arate sufficient to reposition the particle from which the gas wasliberated.
 2. The composition of claim 1 wherein the ice-meltingcomponent comprises a material selected from the group consisting ofcalcium chloride, magnesium chloride, calcium magnesium acetate, sodiumacetate, urea and mixtures thereof.
 3. The composition of claim 1wherein the gas is selected from the group consisting of carbon dioxide,air and nitrogen.
 4. The composition of claim 1 wherein the glassy solidis a material selected from the group consisting of sugar, corn syrupand mixtures thereof.
 5. The composition of claim 1 wherein eachparticle contains both an ice-melting component and a self-dispersingcomponent.
 6. The composition of claim 1 wherein the ice-meltingcomponent and the self-dispersing component are contained in differentparticles.
 7. The composition of claim 1 wherein the particles range inweight from about 0.5 g to about 0.001 g.
 8. The composition of claim 1wherein the particle size ranges in size from about 0.1 mm to about 8mm.
 9. The composition of claim 1 wherein the gas confined within theself-dispersing component is at a pressure of about 400 psi.
 10. Thecomposition of claim 5 wherein the amount of ice-melting componentranges from about 15 to about 35 weight percent of the composition. 11.The composition of claim 6 wherein the ratio of particles containing theself-dispersing component to particles containing the ice-meltingcomponent ranges from about 1:20 to about 1:1.
 12. A particulatecomposition comprising first and second functional components, the firstcomponent comprising a glassy solid containing dispersed pockets ofpressurized gas and the second component comprising a special-usematerial having utility as a deicer.
 13. The composition of claim 12wherein the special-use material is selected from the group consistingof hydrated and anhydrous salts, including calcium chloride, magnesiumchloride, urea, sodium acetate, calcium magnesium acetate, and mixturesthereof.
 14. The composition of claim 12 wherein the first and secondfunctional components are contained in the same particles.
 15. Thecomposition of claim 12 wherein the first and second functionalcomponents are contained in different particles.
 16. The composition ofclaim 14 wherein the second functional component comprises from about 15to about 35 weight percent of the particles.
 17. The composition ofclaim 16 wherein the second functional component comprises from about 20to about 30 weight percent of the particles.
 18. The composition ofclaim 15 having a ratio of particles containing the first functionalcomponent to particles containing the second functional component thatranges from about 1:20 to about 1:1.
 19. The composition of claim 18wherein the ratio of particles containing the first functional componentto particles containing the second functional component that ranges fromabout 1:10 to about 1:3.
 20. The composition of claim 14 wherein theglassy solid comprises about 80 weight percent sugar and about 20 weightpercent urea.
 21. The composition of claim 14 wherein the glassy solidcomprises about 80 weight percent sugar, about 10 weight percent calciumchloride, and about 10 weight percent urea.
 22. The composition of claim14 wherein the glassy solid comprises from about 70 to about 95 weightpercent sugar and from about 5 to about 30 weight percent sodium acetatetrihydrate.
 23. The composition of claim 12 wherein the particles are ina form selected from at least one pellets, prills, flakes and granules.24. The composition of claim 12 wherein the glassy solid is selectedfrom the group consisting of sugar, corn syrup and mixtures thereof. 25.The composition of claim 24 wherein the glassy solid is sugar.
 26. Thecomposition of claim 12 wherein the gas is selected from the groupconsisting of carbon dioxide, air and nitrogen.
 27. The composition ofclaim 26 wherein the gas is carbon dioxide.
 28. The composition of claim14 wherein the glassy solid comprises about 70 weight percent sugar andabout 30 weight percent calcium chloride.